Performance requirements of nuclear power steel plate

Nuclear power steel types cover carbon steel, alloy steel, stainless steel and nickel-based materials, and all have stricter requirements. Because the steel for nuclear island equipment operates in high temperature, high pressure and other environments for a long time, nuclear power steel plates are required to have suitable strength, high resistance and low brittle change temperature (NDT).

The typical nuclear power steels in the world include A508-3, A533 (B, D), BHW35, 16MnD5, SFVV3, etc.

The production of steel for nuclear power is very difficult, and it is close to the limit level of advanced rolling mills at home and abroad. The steel plate for nuclear power is heavy in weight and large in size, and it is ultra-wide, ultra-thick and ultra-heavy. For example, the steel 18MnD5 used for the cylinder body of the CPR1000 steam generator, the single weight of only one steel plate is close to about 40t.

Nuclear power steel plates have strict chemical composition requirements. The steel for nuclear island equipment requires that the content of P and S be less than 0.010% and 0.0005%.

Nuclear power steel sheets have strict mechanical properties requirements. The number of samples has increased significantly, and it is necessary to carry out vertical and horizontal inspections at different positions under different conditions such as high temperature, normal temperature and low temperature after the delivery condition and after the trial simulation of post-weld heat treatment (SPWHT).

Nuclear power steel plates should have excellent structural stability, weldability, and hot and cold workability at operating temperatures, and should have excellent anti-irradiation embrittlement sensitivity under reactor irradiation conditions.

Nuclear power steel plates have strict non-destructive testing requirements. Most of the steel used in nuclear power equipment needs to be subjected to 100% ultrasonic inspection, and the surface of the steel plate needs to be subjected to magnetic particle inspection, which puts forward higher requirements for the qualifications of inspection operators.